Hadoop Cluster:Passwordless SSH setup on CentOs In 3 Steps

Step 1:

[root@pravi ~]# yum install openssh-clients -y 

[root@pravi ~]# ssh-keygen -t rsa
Generating public/private rsa key pair.
Enter file in which to save the key (/root/.ssh/id_rsa):
Enter passphrase (empty for no passphrase):
Enter same passphrase again:
Your identification has been saved in /root/.ssh/id_rsa.
Your public key has been saved in /root/.ssh/id_rsa.pub.
The key fingerprint is:
e7:55:ae:cd:e0:b3:91:4a:36:53:a7:d7:62:d2:9a:d8 root@master.techvantage.com
The key's randomart image is:
+--[ RSA 2048]----+
|                 |
|                 |
|              .  |
|             o   |
|        S . + o  |
|         o + X . |
|          * O B .|
|         o * X . |
|          o E    |
+-----------------+


~/.ssh/id_rsa [private key]
~/.ssh/id_rsa.pub [public key]

Step 2:

[root@master ~]# ssh-copy-id -i ~/.ssh/id_rsa.pub <slave-ip>
Now try logging into the machine, with "ssh 'slave'", and check in:

  .ssh/authorized_keys


to make sure we haven't added extra keys that you weren't expecting.

Step 3

[root@master ~]# ssh <slave-hostname>